Acidic drought scars easing in SA

The Environment Protection Authority (EPA) says there are signs the spreading of crushed limestone is helping improve drought-damaged paddocks along the lower reaches of the Murray.

Highly-acidic underground water surfaced in paddocks from Mannum through to Wellington when higher flows returned to the river during 2010.

A three-hectare trial site has been set up outside Murray Bridge, on a property owned by Barry and Joanne Pfeiffer.

Luke Mosley of the EPA said about 60 tonnes of high-quality crushed limestone had been spread at the site and the effect was positive.

"There are now signs of some improvement in the ground water quality at the trial site," he said.

"By spreading limestone and then irrigating to wash the limestone down into the soil profile, we're trying to neutralise the acid in that ground water before it comes out into the drainage channels.

"Limestone reacts with the acidity in the soil and ground water and it neutralises that acidity so we're hoping with another irrigation event to further wash that limestone into the soil that we'll see further increases in pH."

Mr Mosley cautions more monitoring will be needed to measure the technique's effectiveness.

The limestone trial also involves staff of the Murray-Darling Basin Authority, CSIRO and Dairy SA.

There are 13 other trial sites also being established in the region to consider different ways to restore the paddocks.

Monique White from Dairy SA said she hoped this work could achieve a sustainable future.

"We have a couple of sites which are permanent pasture which is already established, but we're just in the first phase of the project where we're doing soil tests to start the monitoring process," she said.

"There'll be pastures, there'll be hopefully double and triple cropping, so that we can look at how farm businesses can manage with less water in the future and to, I guess, establish a sustainable business so that they can be there to manage the land."

Dairy casualties

The drought almost wiped out the lower Murray's once-prosperous dairy industry.

Dairy SA said the number of dairy farms dropped from about 140 to about 30.

The Pfeiffer property was among the casualties, with lack of water forcing them to sell their dairy cows.

They are now running beef, but warn there will be a long road to recovery, despite higher flows returning to the Murray.

Mr Pfeiffer said the damage to their property from drought showed the importance of returning enough water to the lower reaches of the Murray in the draft Basin plan.

"The plan has got to allow enough water to get through here. Without water height we'll be in the same predicament," he said.

River acid

Highly-acidic water is not just a problem for the farmers, as it is also washing into the River Murray.

The EPA said it was monitoring the problem and ready to deal with any impact on the aquatic ecosystem.

"We've been lucky I guess at the moment that we've had very high flows in the River Murray and that's diluting a lot of the acid drainage water so that process is essentially resulting in there's no risk to any drinking water supplies or public health," Mr Mosley said.

"But we have to keep monitoring and assessing the situation, particularly if we went back to a lower flow situation."

The Water Department said River Murray flows over Lock One had risen to about 37,000 megalitres per day after flooding in eastern Australia.

Daily flows are currently about 60,000 megalitres across the South Australian border.

The state’s entitlement flow for this time of year is about 4,500 megalitres per day.

It's a fundamental human yearning to be a part of something bigger than one's self, and maybe that's what drove my mate Ash to die, far from home, in a bloody foreign war against Islamic State, writes C August Elliott.